package cn.tedu.sp06.fallback;

import cn.tedu.web.util.JsonResult;
import org.springframework.cloud.netflix.zuul.filters.route.FallbackProvider;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.stereotype.Component;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;

@Component
public class OrderFB implements FallbackProvider {
//    指定针对哪个服务应用当前降级类
//    返回服务id
//      item-service 只针对商品降级服务
//       *-对所有服务降级
//       null - 对所有服务降级
    @Override
    public String getRoute() {
        return "order-service";
    }
//      返回的降级响应,封装在response对象中
//      根据自己应用的需求,可以返回任意的响应数据
//          - 错误提示
//          - 缓存数据
//          - 执行业务运算,返回结果
    @Override
    public ClientHttpResponse fallbackResponse(String route, Throwable cause) {
        return new ClientHttpResponse() {
            @Override
            public HttpStatus getStatusCode() throws IOException {
                return HttpStatus.INTERNAL_SERVER_ERROR; //500 , internal error
            }

            @Override
            public int getRawStatusCode() throws IOException {
                return HttpStatus.INTERNAL_SERVER_ERROR.value(); //500
            }

            @Override
            public String getStatusText() throws IOException {
                return HttpStatus.INTERNAL_SERVER_ERROR.getReasonPhrase();  //internal error
            }

            @Override
            public void close() {
//                BAIS 流是内存数组的流,不占用底层系统资源
//                不需要close()释放资源
            }

            @Override
            public InputStream getBody() throws IOException {
//                JasonResult ----- {code:500, msg:系统服务故障,data:null}
               String json= JsonResult.err().code(500).msg("系统服务故障").toString();
                return new ByteArrayInputStream(json.getBytes("UTF-8"));
            }

            @Override
            public HttpHeaders getHeaders() {
                HttpHeaders h = new HttpHeaders();
                h.add("Content-Type","application/json;charset=UTF-8");
                return h;
            }
        };
    }
}
